2015-03-02T23:57:02ZBirth Prevalence of Fatty Acid β-Oxidation Disorders in Iberiahttp://hdl.handle.net/10400.18/2991
Título: Birth Prevalence of Fatty Acid β-Oxidation Disorders in Iberia
Autor: Rocha, Hugo; Castiñeiras, Daisy; Delgado, Carmen; Egea, José; Yahyaoui, Raquel; González, Yolanda; Conde, Manuel; González, Inmaculada; Rueda, Inmaculada; Rello, Luis; Vilarinho, Laura; Cocho, José
Resumo: Mitochondrial fatty acid β-oxidation disorders (FAOD) are main targets for newborn screening (NBS) programs, which are excellent data sources for accurate estimations of disease birth prevalence. Epidemiological data is of key importance for the understanding of the natural history of the disorders as well as to define more effective public health strategies. In order to estimate FAOD birth prevalence in Iberia, the authors collected data from six NBS programs from Portugal and Spain, encompassing the screening of more than 1.6 million newborns by tandem mass spectrometry (MS/MS), and compared it with available data from other populations. The participating NBS programs are responsible for the screening of about 46% of all Iberian newborns. Data reveals that Iberia has one of the highest FAOD prevalence in Europe (1:7,914) and that Portugal has the highest birth prevalence of FAOD reported so far (1:6,351), strongly influenced by the high prevalence of medium-chain acyl-CoA dehydrogenase deficiency (MCADD; 1:8,380), one of the highest ever reported. This is justified by the fact that more than 90% of Portuguese MCADD patients are of Gypsy origin, a community characterized by a high degree of consanguinity. From the comparative analysis of various populations with comparable data other differences emerge, which points to the existence of significant variations in FAOD prevalences among different populations, but without any clear European variation pattern. Considering that FAOD are one of the justifications for MS/MS NBS, the now estimated birth prevalences stress the need to screen all Iberian newborns for this group of inherited metabolic disorders.
Descrição: Disponível online em: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4221301/2014-01-01T00:00:00ZFrom bedside to cell biology: a century of history on lysosomal dysfunctionhttp://hdl.handle.net/10400.18/2985
Título: From bedside to cell biology: a century of history on lysosomal dysfunction
Autor: Coutinho, M.F.; Matos, L.S.; Alves, S.
Resumo: ILysosomal storage disorders (LSDs) are a group of rare genetic diseases, generally caused by a deficiency of specific lysosomal enzymes, which results in abnormal accumulation of undegraded substrates. The first clinical reports describing what were later shown to be LSDs were published more than a hundred years ago. In general, the history and pathophysiology of LSDs has impacted on our current knowledge of lysosomal biology. Classically, depending on the nature of the substrates, LSDs can be divided into different subgroups. The mucopolysaccharidoses (MPSs) are those caused by impaired degradation of glycosaminoglycans (GAGs). Amongst LSDs, the MPSs are a major group of pathologies with crucial historical relevance, since their study has revealed important biological pathways and highlighted interconnecting pathological cascades which are still being unveiled nowadays. Here we review the major historical discoveries in the field of LSDs and their impact on basic cellular knowledge and practical applications. Attention will be focused on the MPSs, with occasional references to other LSDs. We will show as studies on the metabolic basis of this group of diseases have increased our knowledge of the complex degradative pathways associated with the lysosome and established the basis to the development of specific therapeutic approaches aiming at correcting or, at least ameliorating their associated phenotypes.2014-09-29T00:00:00ZThe hepcidin gene promoter nc.-1010C > T; -582A > G haplotype modulates serum ferritin in individuals carrying the common H63D mutation in HFE genehttp://hdl.handle.net/10400.18/2982
Título: The hepcidin gene promoter nc.-1010C > T; -582A > G haplotype modulates serum ferritin in individuals carrying the common H63D mutation in HFE gene
Autor: Silva, B.; Pita, L.; Gomes, S.; Gonçalves, J.; Faustino, P.
Resumo: Hereditary hemochromatosis is an autosomal recessive disorder characterized by severe iron overload. It is usually associated with homozygosity for the HFE gene mutation c.845G > A; p.C282Y. However, in some cases, another HFE mutation (c.187C > G; p.H63D) seems to be associated with the disease. Its penetrance is very low, suggesting the possibility of other iron genetic modulators being involved. In this work, we have screened for HAMP promoter polymorphisms in 409 individuals presenting normal or increased serum ferritin levels together with normal or H63D-mutated HFE genotypes. Our results show that the hepcidin gene promoter TG haplotype, originated by linkage of the nc.-1010C > T and nc.-582A > G polymorphisms, is more frequent in the HFE_H63D individuals presenting serum ferritin levels higher than 300 μg/L than in those presenting the HFE_H63D mutation but with normal serum ferritin levels or in the normal control group.Moreover, it was observed that the TG haplotype was associated to increased serum ferritin levels in the overall pool of HFE_H63D individuals. Thus, our data suggest that screening for these polymorphisms could be of interest in order to explain the phenotype. However, this genetic condition seems to have no clinical significance.2014-12-01T00:00:00ZSilencing of the tumor suppressor gene WNK2 is associated with upregulation of MMP2 and JNK in gliomashttp://hdl.handle.net/10400.18/2981
Título: Silencing of the tumor suppressor gene WNK2 is associated with upregulation of MMP2 and JNK in gliomas
Autor: Costa, Ângela; Pinto, Filipe; Martinho, Olga; Oliveira, Maria José; Jordan, Peter; Reis, Rui Manuel
Resumo: Matrix metalloproteinases (MMPs) are proteolytic enzymes that degrade extracellular matrix (ECM), thus assisting invasion. Upregulation of MMPs, frequently reported in gliomas, is associated with aggressive behavior. WNK2 is a tumor suppressor gene expressed in normal brain, and silenced by promoter methylation in gliomas. Patients without WNK2 exhibited poor prognosis, and its downregulation was associated with increased glioma cell invasion.
Here we showed that MMP2 expression and activity are increased in glioma cell lines that do not express WNK2. Also, WNK2 inhibited JNK, a process associated with decreasing levels of MMP2. Thus, WNK2 promoter methylation and silencing in gliomas is associated with increased JNK activation and MMP2 expression and activity, thus explaining in part tumor cell invasion potential.2014-12-22T00:00:00Z